leds: as3645a: Fix error return code in as3645a_parse_node()

Return error code -ENODEV rather than '0' when the indicator node can not
be found.

Fixes: a56ba8fbcb55 ("media: leds: as3645a: Add LED flash class driver")
Reported-by: Hulk Robot <[e-mail]>
Acked-by: Sakari Ailus <[e-mail]>
Signed-off-by: Zhen Lei <[e-mail]>
Signed-off-by: Pavel Machek <[e-mail]>

drivers/leds/leds-as3645a.c

···
 	if (!flash->indicator_node) {
 		dev_warn(&flash->client->dev,
 			 "can't find indicator node\n");
+		rval = -ENODEV;
 		goto out_err;
 	}